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O: Oberflächenphysik
O 33: Methodisches (Experiment und Theorie)
O 33.4: Vortrag
Donnerstag, 29. März 2001, 16:15–16:30, M
Partial Electron Yield Measurements at Ambient and High Pressure - A New Development in X-Ray Absorption Spectroscopy — •Antje Vollmer1, Gareth E. Derbyshire2, John D. Lipp2, J. Edmond Bateman2, Richard Stephenson2, Sven L. M. Schroeder3, and Trevor Rayment1 — 1Dept.of Chemistry, University of Cambridge, Lensfield Road, Cambridge, CB2 1EW, UK — 2Rutherford Appleton Laboratories, Chilton, Didcot, Oxon, OX11 0QX, UK — 3Inst. f. Chemie, FU Berlin, Takustr.3, 14195 Berlin, Germany
We present the operation and first results of a new type of proportional electron counter (gas microstrip detector GMSD) originally developed for high energy collider physics [1][2] and its first applications in surface science. GMSDs allow energy selective filtering of the electron signal and thus provide a significant improvement of surface sensitivity relative to conventional electron yield experiments [3]. We report upon the EXAFS of thin NiO layers on polycrystalline, diamond -polished Ni samples, depth profiling experiments and investigations into the effect of different gas compositions (He, Isobutane, H2, O2, CO, CO2) in the detector. Recent investigations have shown that GMSDs are therefore suitable for in situ EXAFS studies of catalytic reactions on surfaces. [1] J.E. Bateman et al, Nucl. Instrum. Methods A 348, 372 (1994) [2] A. Oed, Nucl. Instrum. Methods A 263, 351 (1988) [3] T. Rayment et al, Rev. Sci. Instrum. 71 (2000) 3640